public class Demo {

    public static int count = 0;

    public static void main(String[] args) throws InterruptedException {

        Object locker = new Object();
        Thread t1 = new Thread(() -> {
            for (int i = 0; i < 50000; i++) {
                synchronized (locker) {
                    count++;

                }
            }
            System.out.println("t1 线程结束");
        });

        Thread t2 = new Thread(() -> {
            for (int i = 0; i < 50000; i++) {
                synchronized (locker) {
                    count++;

                }

            }
            System.out.println("t2 线程结束");

        });

        t1.start();
        t2.start();

        t1.join();
        t2.join();
        System.out.println(count);



    }
}
